linux/drivers/mfd/max8925-i2c.c

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/*
* I2C driver for Maxim MAX8925
*
* Copyright (C) 2009 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/mfd/max8925.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#define RTC_I2C_ADDR 0x68
#define ADC_I2C_ADDR 0x47
static inline int max8925_read_device(struct i2c_client *i2c,
int reg, int bytes, void *dest)
{
int ret;
if (bytes > 1)
ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
else {
ret = i2c_smbus_read_byte_data(i2c, reg);
if (ret < 0)
return ret;
*(unsigned char *)dest = (unsigned char)ret;
}
return ret;
}
static inline int max8925_write_device(struct i2c_client *i2c,
int reg, int bytes, void *src)
{
unsigned char buf[bytes + 1];
int ret;
buf[0] = (unsigned char)reg;
memcpy(&buf[1], src, bytes);
ret = i2c_master_send(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
return 0;
}
int max8925_reg_read(struct i2c_client *i2c, int reg)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char data = 0;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
if (ret < 0)
return ret;
else
return (int)data;
}
EXPORT_SYMBOL(max8925_reg_read);
int max8925_reg_write(struct i2c_client *i2c, int reg,
unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_reg_write);
int max8925_bulk_read(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_read);
int max8925_bulk_write(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_write);
int max8925_set_bits(struct i2c_client *i2c, int reg,
unsigned char mask, unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char value;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &value);
if (ret < 0)
goto out;
value &= ~mask;
value |= data;
ret = max8925_write_device(i2c, reg, 1, &value);
out:
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_set_bits);
static const struct i2c_device_id max8925_id_table[] = {
{ "max8925", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, max8925_id_table);
static int __devinit max8925_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct max8925_platform_data *pdata = client->dev.platform_data;
static struct max8925_chip *chip;
if (!pdata) {
pr_info("%s: platform data is missing\n", __func__);
return -EINVAL;
}
chip = kzalloc(sizeof(struct max8925_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
chip->i2c = client;
chip->dev = &client->dev;
i2c_set_clientdata(client, chip);
dev_set_drvdata(chip->dev, chip);
mutex_init(&chip->io_lock);
chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
i2c_set_clientdata(chip->rtc, chip);
chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
i2c_set_clientdata(chip->adc, chip);
device_init_wakeup(&client->dev, 1);
max8925_device_init(chip, pdata);
return 0;
}
static int __devexit max8925_remove(struct i2c_client *client)
{
struct max8925_chip *chip = i2c_get_clientdata(client);
max8925_device_exit(chip);
i2c_unregister_device(chip->adc);
i2c_unregister_device(chip->rtc);
kfree(chip);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int max8925_suspend(struct device *dev)
{
struct i2c_client *client = container_of(dev, struct i2c_client, dev);
struct max8925_chip *chip = i2c_get_clientdata(client);
if (device_may_wakeup(dev) && chip->wakeup_flag)
enable_irq_wake(chip->core_irq);
return 0;
}
static int max8925_resume(struct device *dev)
{
struct i2c_client *client = container_of(dev, struct i2c_client, dev);
struct max8925_chip *chip = i2c_get_clientdata(client);
if (device_may_wakeup(dev) && chip->wakeup_flag)
disable_irq_wake(chip->core_irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume);
static struct i2c_driver max8925_driver = {
.driver = {
.name = "max8925",
.owner = THIS_MODULE,
.pm = &max8925_pm_ops,
},
.probe = max8925_probe,
.remove = __devexit_p(max8925_remove),
.id_table = max8925_id_table,
};
static int __init max8925_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&max8925_driver);
if (ret != 0)
pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
return ret;
}
subsys_initcall(max8925_i2c_init);
static void __exit max8925_i2c_exit(void)
{
i2c_del_driver(&max8925_driver);
}
module_exit(max8925_i2c_exit);
MODULE_DESCRIPTION("I2C Driver for Maxim 8925");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");